With rapid development of information technologies, people have increasingly higher requirements for network communications, and wish to break restrictions of different regional or objective conditions, to achieve a goal that anyone can communicate with anyone in any way anywhere at any time. As an important part of personal communications, a wireless local area network (LAN) has contributed to a new wave of mobile computing, and will be widely used in reality and future social life. The LAN replaces the traditional cable with electromagnetic waves in the air for information transmission, and can be used as extension, supplement or replacement of the traditional cable network. In comparison, the LAN has advantages in respects of mobility, flexibility, scalability and economical efficiency. However, wireless communications also face a larger problem, that is, channel congestion. A channel is a passage of information transmission between a source and a destination, which is achieved through a transmission media or a transmission medium.
In order to solve the problem of channel congestion, a fixed channel assignment method and a dynamic channel assignment method are provided. The process of the fixed channel assignment method is briefly introduced as follows: dividing an entire service area into a certain number of cells, each cell being equipped with a certain number of channels according to a certain channel multiplexing form, equivalent to completely isolating the channels between different cells of a cell group, and such a fixed channel assignment method can meet certain signal quality. A call admission control policy of fixed channel assignment is as follows: when a new call requires admission, the call is accepted if a corresponding cell has an idle channel. Such a manner cannot automatically adjust channel assignment with business conditions and user distribution. The process of the dynamic channel assignment method is briefly introduced as follows: all channel resources are completely shared, when there is admission of a new call, and in channels that meet the minimum carrier-to-interference ratio threshold, an appropriate channel is selected according to a certain algorithm to serve admission of the call; although such a manner can achieve dynamic assignment of the channel, computation and control complexity thereof are high.